Traditionally, in the event of extreme weather or a disaster scenario, the NOAA Weather Radio service, or a similar agency, broadcasts emergency alert warnings over dedicated FM radio bands to notify residents of a particular geographical region of the impending threat. Using Same Area Message Encoding technology (SAME), these alerts are sent out as a digital set of information encoded for transmission over analog airwaves. The digital information prefixes the alert with pertinent details about the emergency, including information with regards to the type of emergency, the geographical areas affected by the emergency as well as the expected duration of the emergency.
This information may also be used to determine when audio data concerning the event and the regions affect will be broadcasted. Conventional radios designed specifically for these alerts are generally stationary devices that must always be powered on and tuned into a specific channel and wait for alerts that relate to a fixed geographical region. Furthermore, as these devices listen to every alert broadcasted over the FM radio band, they consume power unnecessarily. For radios that are portable, this conventional mode of operation further results in wasted battery life.